diff --git a/tests/command_zone_tests/counter_command_auth_test.cpp b/tests/command_zone_tests/counter_command_auth_test.cpp
index e7905428d..2b76509dd 100644
--- a/tests/command_zone_tests/counter_command_auth_test.cpp
+++ b/tests/command_zone_tests/counter_command_auth_test.cpp
@@ -24,8 +24,6 @@ Server_Counter makeCounter(int id, int count)
 }
 } // namespace
 
-// evaluateDelCounter
-
 TEST(EvaluateDelCounter, RejectsWhenGameNotStarted)
 {
     Server_Counter counter = makeCounter(UserCounterId, 0);
@@ -70,8 +68,6 @@ TEST(EvaluateDelCounter, GameNotStartedTakesPrecedenceOverTaxGuard)
               Response::RespGameNotStarted);
 }
 
-// evaluateSetCounterActive
-
 TEST(EvaluateSetCounterActive, RejectsWhenGameNotStarted)
 {
     Server_Counter counter = makeCounter(CounterIds::CommanderTax, 0);
@@ -150,8 +146,6 @@ TEST(EvaluateSetCounterActive, RejectsDisablingPartnerTaxWhenAccumulated)
               Response::RespContextError);
 }
 
-// evaluateCreateCounter
-
 TEST(EvaluateCreateCounter, RejectsWhenGameNotStarted)
 {
     EXPECT_EQ(Server_Player::evaluateCreateCounter(/*gameStarted=*/false, /*playerConceded=*/false, "mycounter"),
@@ -183,8 +177,6 @@ TEST(EvaluateCreateCounter, AllowsOrdinaryNames)
     EXPECT_EQ(Server_Player::evaluateCreateCounter(true, false, ""), Response::RespOk);
 }
 
-// evaluateModifyCounter (shared by cmdIncCounter / cmdSetCounter)
-
 TEST(EvaluateModifyCounter, RejectsWhenGameNotStarted)
 {
     Server_Counter counter = makeCounter(UserCounterId, 0);
@@ -238,6 +230,13 @@ TEST(EvaluateModifyCounter, AllowsActiveTaxCounter)
               Response::RespOk);
 }
 
+TEST(EvaluateModifyCounter, RejectsMissingTaxCounter)
+{
+    EXPECT_EQ(Server_Player::evaluateModifyCounter(true, false, /*commandZoneEnabled=*/true, CounterIds::CommanderTax,
+                                                   /*counter=*/nullptr),
+              Response::RespNameNotFound);
+}
+
 int main(int argc, char **argv)
 {
     ::testing::InitGoogleTest(&argc, argv);